Convert GetList from SingleDocument to QueryPage (elastic/elasticsearch#408)

Related to elastic/elasticsearch#314

Original commit: elastic/x-pack-elasticsearch@40702a3d5b

elasticsearch/src/main/java/org/elasticsearch/xpack/prelert/action/GetListAction.java

@@ -34,10 +34,11 @@ import org.elasticsearch.common.xcontent.XContentParser;
 import org.elasticsearch.rest.RestStatus;
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.transport.TransportService;
+import org.elasticsearch.xpack.prelert.job.persistence.QueryPage;
 import org.elasticsearch.xpack.prelert.lists.ListDocument;
-import org.elasticsearch.xpack.prelert.utils.SingleDocument;
 
 import java.io.IOException;
+import java.util.Collections;
 import java.util.Objects;
 
 import static org.elasticsearch.action.ValidateActions.addValidationError;
@@ -125,44 +126,44 @@ public class GetListAction extends Action<GetListAction.Request, GetListAction.R
 
     public static class Response extends ActionResponse implements StatusToXContent {
 
-        private SingleDocument<ListDocument> response;
+        private QueryPage<ListDocument> lists;
 
-        public Response(SingleDocument<ListDocument> document) {
-            this.response = document;
+        public Response(QueryPage<ListDocument> lists) {
+            this.lists = lists;
         }
 
         Response() {
         }
 
-        public SingleDocument<ListDocument> getResponse() {
-            return response;
+        public QueryPage<ListDocument> getLists() {
+            return lists;
         }
 
         @Override
         public void readFrom(StreamInput in) throws IOException {
             super.readFrom(in);
-            response = new SingleDocument<>(in, ListDocument::new);
+            lists = new QueryPage<>(in, ListDocument::new);
         }
 
         @Override
         public void writeTo(StreamOutput out) throws IOException {
             super.writeTo(out);
-            response.writeTo(out);
+            lists.writeTo(out);
         }
 
         @Override
         public RestStatus status() {
-            return response.status();
+            return lists.count() == 0 ? RestStatus.NOT_FOUND : RestStatus.OK;
         }
 
         @Override
         public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
-            return response.toXContent(builder, params);
+            return lists.doXContentBody(builder, params);
         }
 
         @Override
         public int hashCode() {
-            return Objects.hash(response);
+            return Objects.hash(lists);
         }
 
         @Override
@@ -174,7 +175,7 @@ public class GetListAction extends Action<GetListAction.Request, GetListAction.R
                 return false;
             }
             Response other = (Response) obj;
-            return Objects.equals(response, other.response);
+            return Objects.equals(lists, other.lists);
         }
 
         @SuppressWarnings("deprecation")
@@ -183,9 +184,7 @@ public class GetListAction extends Action<GetListAction.Request, GetListAction.R
             try {
                 XContentBuilder builder = XContentFactory.jsonBuilder();
                 builder.prettyPrint();
-                builder.startObject();
                 toXContent(builder, EMPTY_PARAMS);
-                builder.endObject();
                 return builder.string();
             } catch (Exception e) {
                 // So we have a stack trace logged somewhere
@@ -231,17 +230,19 @@ public class GetListAction extends Action<GetListAction.Request, GetListAction.R
                 public void onResponse(GetResponse getDocResponse) {
 
                     try {
-                        SingleDocument<ListDocument> responseBody;
+                        QueryPage<ListDocument> responseBody;
                         if (getDocResponse.isExists()) {
                             BytesReference docSource = getDocResponse.getSourceAsBytesRef();
                             XContentParser parser = XContentFactory.xContent(docSource).createParser(docSource);
                             ListDocument listDocument = ListDocument.PARSER.apply(parser, () -> parseFieldMatcher);
-                            responseBody = new SingleDocument<>(ListDocument.TYPE.getPreferredName(), listDocument);
-                        } else {
-                            responseBody = SingleDocument.empty(ListDocument.TYPE.getPreferredName());
-                        }
+                            responseBody = new QueryPage<>(Collections.singletonList(listDocument), 1, ListDocument.RESULTS_FIELD);
+
                             Response listResponse = new Response(responseBody);
                             listener.onResponse(listResponse);
+                        } else {
+                            this.onFailure(QueryPage.emptyQueryPage(ListDocument.RESULTS_FIELD));
+                        }
+
                     } catch (Exception e) {
                         this.onFailure(e);
                     }

elasticsearch/src/main/java/org/elasticsearch/xpack/prelert/lists/ListDocument.java

@@ -25,6 +25,9 @@ public class ListDocument extends ToXContentToBytes implements Writeable {
     public static final ParseField ID = new ParseField("id");
     public static final ParseField ITEMS = new ParseField("items");
 
+    // For QueryPage
+    public static final ParseField RESULTS_FIELD = new ParseField("lists");
+
     @SuppressWarnings("unchecked")
     public static final ConstructingObjectParser<ListDocument, ParseFieldMatcherSupplier> PARSER = new ConstructingObjectParser<>(
             TYPE.getPreferredName(), a -> new ListDocument((String) a[0], (List<String>) a[1]));

elasticsearch/src/test/java/org/elasticsearch/xpack/prelert/action/GetListActionResponseTests.java

@@ -6,6 +6,7 @@
 package org.elasticsearch.xpack.prelert.action;
 
 import org.elasticsearch.xpack.prelert.action.GetListAction.Response;
+import org.elasticsearch.xpack.prelert.job.persistence.QueryPage;
 import org.elasticsearch.xpack.prelert.lists.ListDocument;
 import org.elasticsearch.xpack.prelert.support.AbstractStreamableTestCase;
 import org.elasticsearch.xpack.prelert.utils.SingleDocument;
@@ -16,13 +17,11 @@ public class GetListActionResponseTests extends AbstractStreamableTestCase<GetLi
 
     @Override
     protected Response createTestInstance() {
-        final SingleDocument<ListDocument> result;
-        if (randomBoolean()) {
-            result = SingleDocument.empty(ListDocument.TYPE.getPreferredName());
-        } else {
-            result = new SingleDocument<>(ListDocument.TYPE.getPreferredName(),
-                    new ListDocument(randomAsciiOfLengthBetween(1, 20), Collections.singletonList(randomAsciiOfLengthBetween(1, 20))));
-        }
+        final QueryPage<ListDocument> result;
+
+        ListDocument doc = new ListDocument(
+                randomAsciiOfLengthBetween(1, 20), Collections.singletonList(randomAsciiOfLengthBetween(1, 20)));
+        result = new QueryPage<>(Collections.singletonList(doc), 1, ListDocument.RESULTS_FIELD);
         return new Response(result);
     }
 

elasticsearch/src/test/resources/rest-api-spec/test/list_crud.yaml

@@ -19,10 +19,6 @@ setup:
       xpack.prelert.get_lists:
         list_id: "do_not_exist"
 
-  - match: { exists:   false }
-  - match: { type:    "list"   }
-  - is_false: document
-
 ---
 "Test get list API":
 
@@ -30,10 +26,9 @@ setup:
       xpack.prelert.get_lists:
         list_id: "foo"
 
-  - match: { exists:   true }
-  - match: { type:    "list"   }
+  - match: { count:   1 }
   - match:
-      document:
+      lists.0:
         id: "foo"
         items: ["abc", "xyz"]
 
@@ -52,10 +47,9 @@ setup:
       xpack.prelert.get_lists:
         list_id: "foo2"
 
-  - match: { exists:   true }
-  - match: { type:    "list"   }
+  - match: { count:   1 }
   - match:
-      document:
+      lists.0:
         id: "foo2"
         items: ["abc", "xyz"]